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161.
ABSTRACT

Traditionally, prospective resource parents must attend all preservice training in person. Although live sessions are necessary for screening applicants, instructional portions of training could be enhanced by Web-based sessions. This pilot study compares the effectiveness of online and classroom versions of one session from a widely used preservice training program. Ninety-two individuals enrolled in the program in two states were randomly assigned to a treatment group that viewed an online version of the class on child abuse and neglect or to a comparison group that took the same class in person. Written questionnaires were completed before and after the class. Significant group differences on knowledge of child maltreatment and empathy toward birth parents plus high user satisfaction were hypothesized. Analysis of covariance results showed the online training was more effective than the live training at increasing knowledge. Multivariate analysis of covariance findings on empathy were not significant but trended toward greater empathy for the online group. Feedback indicated high satisfaction with the online course. The finding that online instruction is more effective than live instruction has positive implications for practice, because Web-based training offers advantages like standardizing instruction, cutting agency and trainee costs, and providing greater flexibility.  相似文献   
162.
Response surface methodology is widely used for developing, improving, and optimizing processes in various fields. In this article, we present a method for constructing three-level designs in order to explore and optimize response surfaces combining orthogonal arrays and covering arrays in a particular manner. The produced designs achieve the properties of rotatability, predictive performance and efficiency for the estimation of a second-order model.  相似文献   
163.
Quality of life (QOL) has become an important component of health. By using the methodology of psychometric theory, we examine the item properties of the WHOQOL-BRIEF. Samejima’s graded response model with natural metrics of the logistic response function was fitted. The results showed items with negative natures were less discriminating. Items written in a specific way were more suitable to assess certain subgroups. The national items showed variation in discriminatory power. Questions measuring objective and specific issues performed worse than items assessing general aspects of the QOL.  相似文献   
164.
Severe departures from normality occur frequently for null distributions of statistics associated with applications of mulLi-response permutation procedures (MRPP) for either small or large finite populations. This paper describes the commonly encountered situation associated with asymptotic non-normality for null distributions of MRPP statistics which does not depend on the underlying multivariate distribution. In addition, this paper establishes the existence of a non-degenerate underlying distribution for which the null distributions of MRPP statistics are asymptotically non-normal for essentially all size structure configurations. It is known that MRPP statistics are symmetric versions of a broader class of statistics, most of which are asymmetric. Because of the non-normality associated with null distributions of MRPP statistics, this paper includes necessary results for inferences based on the exact first three moments of anv statistic in this broader class (analogous to existing results for MRPP statistics).  相似文献   
165.
Standard resulrs on the extrema of quotients of quadratic forms are extended to the non-negative definite case. The maximum and the set over which it is achieved are characterized explicitly both in terms of generalized inverse matrices and generalized eigenvalues. These results become the basis of Scheffe type multiple comparisons in the usual way. To demonstrate their application to statistics with singular covariance matrices, the method is detailed for Mantel-Haenszel, Breslow, and Cox statistics. An example is presented illustrating a situation where the proposed Scheffe type comparisons may be better than the pairwise method.  相似文献   
166.
英国小说家艾丽丝·默多克的代表作《黑王子》是一部具有实验性质的小说,从多个层面探讨了生活的本质,艺术与生活的关系。包括情节、引喻、叙事策略以及结构安排等构成了小说的召唤结构,共同作用于读者的阅读活动,使读者能够自觉地建构小说的意义,对其哲学内涵作出反应。  相似文献   
167.
疑问代词除了表示询问、任指和虚指外,还有一个重要的用法,即用在反问句中表示否定。文章以"怎么"为例,根据其出现的语言环境,分类考察了"怎么+AD+VP"用于表示否定出现的句法环境、语义以及功能,并从反问句的句法机制和主观性因素的角度分析了其表示否定意义的原因。  相似文献   
168.
对于所采集的条码图像,为了适应实时性的要求,以得到不同光照条件下的最佳阈值,该文提出了把直方图双峰法、OTSU法及NLNiblack阈值法结合起来的改进的自适应阈值法。实验证明了该方法具有高效性和稳定性。为了在条码分割图像中获取QR码的4个顶点,首先,根据3个位置探测图形的特性提出了一种新的方法以求取对应的3个顶点,同时利用QR码的特征提出挖空算法获取条码的边缘,再采用过已知点的Hough变换得到第4个顶点。实验证明该算法在各种采集条件下可有效地得到QR码的4个顶点。  相似文献   
169.
给出了分析二维对流-扩散方程FTCS显格式(时间向前,空间中心的差分格式)稳定条件的一种方法.这种方法可用于分析一维到高维对流-扩散方程差分格式的稳定性.  相似文献   
170.
In this paper we consider the problem of obtaining best linear unbiased estimators of individual response coefficients in a Random Coefficient Linear Regression (RCR} Model, comparing alternative estimators for these response vectors through a simulation study. We also provide an empirical example that illustrates the estimation procedure proposed here.  相似文献   
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